This application claims the priority of Korean Patent Application No. 10-2004-0070235, filed on Sep. 3, 2004 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.
1. Field of the Invention
The present invention relates to an apparatus and method for manufacturing a semiconductor package, and more particularly, to a die attaching apparatus, and a system and method for cleaning the die attaching apparatus.
2. Description of the Related Art
Chips produced in the form of a wafer are packaged such that they are protected from external shocks and properly mounted on a board. A process of bonding the chips on a substrate during a package manufacturing process is called a die attaching process. Specifically, dies individualized through a sawing process are attached onto a substrate, such as a lead frame, by means of an adhesive, such as an epoxy tape.
Referring to FIG. 1, the die attaching apparatus includes a press unit 20, which generates a pressure, and an attaching unit 30, which attaches dies 16 to a substrate 14 using the pressure. The attaching unit 30, which is a single unit comprising a plurality of parts, operates at a pressure. The press unit 20 receives an external pressure and causes a hydraulic pressure generating unit 36 to generate a hydraulic pressure. Since the hydraulic pressure is isotropic, a uniform pressure is generated in all directions. Here, the hydraulic pressure is measured by a hydraulic pressure sensing unit 32.
The hydraulic pressure is transferred downward to lower a plurality of plungers 42. The lowered plungers 42 apply the pressure to the dies 16 located on the substrate 14. Cylindrical collets (not shown) may protrude from lower ends of the plungers 42 directly contacting the dies 14. Here, the distance between adjacent plungers 42 is adjusted by a distance between adjacent plunger guides of a plurality of plunger guides 48. A heater 46 for heating the plungers 42, and support bodies 44 may be disposed on a lower side of the unit 30 near the plungers 42. After a die attaching process ends, the press unit 20 is lifted and the plungers 42 and the hydraulic pressure generating unit 36 are returned to their own positions using springs 38. Reference numeral 34 denotes a main block.
Here, since the attaching unit 30 is a single unit, an entire attaching unit 30 is demounted or mounted when components need to be replaced. If the type of a package is changed, the size of the plungers 42 and the distance between the plungers 42 are changed. The distance between the plungers 42 can be adjusted by replacing the plunger guides 48. However, in order to replace the plunger guides 48, the whole attaching unit 30 should be demounted and removed and then a new attaching unit 30 should be mounted in its place because the attaching unit 30 including the plunger guides 48 is a single unit. Accordingly, repair/replacement costs are high and all processes involving the attaching unit 30 must be stopped while the new attaching unit 30 is installed.
In the meantime, the substrate 14, which is a stripe-shaped, for example, in the form of a lead frame, is placed on a heat plate 12 that is formed on a worktable 10, and the dies 16 are mounted on the substrate 14. On the dies 16 and the substrate 14 supplied for the die attaching process, there are formed micro circuits and wire bonding pads. Since the collet and the heat plate 12 may be contaminated by foreign substances residing in the circuits and the pads during the die attaching process, the surface of the collet and the heat plate 12 should be periodically cleaned. However, a conventional cleaning process, which is manually or automatically performed, does not achieve satisfactory cleaning results. Accordingly, there is a demand for developing a new cleaning system and method, which can achieve more improved cleaning results and prevent secondary pollution caused by dust produced during a cleaning process.